Briar's friend, a street thief from the slums, falls ill and asks for help. Briar finds himself powerless and brings his mentor Rosethorn to her. They do not yet know that this is only one of the first victims of the magical plague epidemic that is about to overwhelm Emelan, and Briar will be part of a team of researchers thrown into the fight against the virus. Medicines do not help, the number of cases is growing, and infection in such a situation practically guarantees death...